Abstract: A new and improved gas turbine engine including a gas generator and a power turbine is disclosed. The power turbine includes a first rotor having a plurality of first turbine blade rows extending radially outwardly therefrom, and a second rotor having a plurality of second turbine blade rows extending radially inwardly therefrom. The power turbine is supported aft of the gas generator and is effective for receiving combustion gases therefrom and expanding the gases through the first and second turbine blade rows for extracting substantially all output power therefrom for driving the first and second rotors in counterrotating directions.

Abstract: The invention comprises a wall having first and second spaced surfaces, and a first plane disposed therebetween which includes first and second coplanar and orthogonal axes. A passage extends between the first and second surfaces and includes a portion having longitudinal axis disposed at an acute angle to the first plane, the first section being disposed perpendicularly to the longitudinal axis and the second section being disposed parallel to the first plane. The passage first section is generally elliptical and the passage second section is generally circular.

Abstract: An improved blade mounting arrangement for a gas turbine engine with a turbine and an annular flowpath therethrough is disclosed. The improvement comprises a one-piece outer casing and a one-piece inner casing bounding the flowpath. The outer casing has a plurality of circumferential recesses disposed therein with each of the recesses having first and second axially opposite circumferential slots. A plurality of first turbine blades, each with axially facing tangs on a mounting platform, mate with the slots in the outer casing recess. The inner casing has a plurality of recesses disposed therein, each of the recesses including a forward circumferential slot and concentric aft radially outer and radially inner circumferential slots. A plurality of second turbine blades, each with forward and aft axially facing tangs on a mounting platform, mate with respective ones of forward slot and radially outer slot in the inner casing recess.

Abstract: A method and system for controlling rotor blade tip clearances in a gas turbine engine is disclosed. A flow of heat transfer fluid is supplied to the rotor. The temperature of the flow is controlled as a function of the heat carrying capacity of the fluid.

Abstract: A system for controlling rotor blade tip clearances in a gas turbine engine supplies both heating air and cooling air to the rotor bore. The heating air flow is controlled by a valve and the cooling air flow is not controlled.

Abstract: An apparatus for measuring force has a resistive element which has an electrical resistance which varies as a function of force applied to the transducer. An electrical output signal related to the resistance of the element has a sufficient magnitude so that it can be fed directly to processing circuitry without any amplification. This is accomplished by modulating the electrical power supplied to the resistive element to enhance the electrical output signal.

Abstract: A gas turbine rotor blade platform sealing and damping system has elongated symmetrical insert elements of equilateral triangular cross-section loosely received within complementary shaped pockets at the spacing gaps between opposing convex and concave airfoil side edges of adjacently mounted blade platforms. The inserts and pockets are relatively configured to provide self-orientation of the inserts into gap sealing and vibration damping engagement with the platform edges when acted upon by centrifugal force due to rotor rotation. The convex platform edge is thickened at the point of closest proximity with the convex side of the airfoil. Alternative embodiments utilize insert grooves for increased leakage of cooling gas past the platform edges and incorporate a central bore for mass reduction.

Abstract: A mounting assembly for supporting stator vane platforms formed in an extended arc length, in a compressor casing, comprising a circumferential flange formed in the compressor casing having spaced clamp arms, a flange carrier on each stator vane platform having a surface which is formed with a plurality of radially outwardly extending wedge lock elements, and locking springs having inner and outer sides each formed with wedge lock elements extending radially outwardly therefrom. In order to mount the stator vane platform on the compressor casing, the locking springs are placed in an "unlocked" position on the flange of a stator vane platform wherein the wedge lock elements on the inner side of the locking spring extend between adjacent wedge lock elements on the flange. The vane platform flange and locking spring are then inserted as a unit between the clamp arms of the compressor casing.

Abstract: A steam piston balance means for a turbine engine comprises, in one form, a pressure chamber and means for supplying steam to the chamber to apply a force to walls of the chamber. The chamber is defined, in part, by an inner surface portion of a member connected and rotating with a portion of a thrust bearing whereby pressure force applied on the inner surface in turn applies a tractor force on the thrust bearing.

Abstract: An apparatus for the inspection of a stack of cylindrical objects such as roller bearings, uses an eddy current probe. The probe is positioned at an angle with respect to the surfaces of the objects in order to achieve an acceptable signal and then the objects are rotated while the probe is advanced along them to fully scan the surfaces.

Abstract: Blade carrying means for variable pitch propulsor blades of a gas turbine engine are disclosed. The blade carrying means comprise dual, axially positioned rings and a plurality of generally cylindrical bearing journals supported between the rings. Each of the journals has a radially outer and inner edge and is adapted to support a single propulsor blade. The blade carrying means also comprise stiffening means, such as a bulkhead attached to the inner edge, for preventing distortion of the journal inner edge.

Abstract: The invention relates to a type of proximity sensor. In one form, two sinusoidal signals travel along two transmission lines near an object. When the distance between one or both of the lines and the object changes, the speed of travel of one or both of the signals changes. There is a correlation between the speed change and the distance, thus allowing one to infer distance from speed change. One way to measure the speed change is to measure the phase relationship between the two signals.

Abstract: An improved air swirler and fuel injector for a gas turbine combustor system employs primary fuel injection into a primary recirculation combustion zone supplied by an inner annulus of swirling air at high fuel-air ratio under low power conditions. A selectively staged secondary fuel flow is supplied into an outer annulus downstream of secondary air swirlers supplying a secondary recirculation zone for combustion at higher fuel flows but lower fuel-air ratios under high power conditions. The secondary fuel flow may be separately injected into the outer annulus through conduit means extending through the primary air swirler vanes. Alternatively, the secondary fuel flow may be combined with the primary fuel in the fuel injector body and the momentum due to mass flow used to inject the fuel into the outer annulus.

Abstract: An air dispensing arrangement within a gas turbine engine in which the energy of the pressurized air exiting the compressor is nonuniform. The higher energy pressurized air is dispensed by at least one conduit to the combustor and to other components, the higher energy air providing an improved cooling capability over the lower energy air. Provision is also made to employ the lower energy air for uses such as the dilution of the combustor gases.

Abstract: In accordance with a preferred, exemplary embodiment of the invention, a method of forming a blisk from a workpiece is disclosed. The workpiece includes a blank having oppositely facing first and second faces defined by a radially inner housing, a radially outer top, a first edge, and a second edge. The method comprises the steps of:positioning first and second electrodes adjacent to the first and second faces, respectively, of the blank;supplying a positive voltage to the blank and a negative voltage to the first and second electrodes;channeling an electrolyte between the blank and the first and second electrodes for electrochemically machining the blank;moving the first and second electrodes toward the first and second faces of the blank; andmoving the workpiece toward the first and second electrodes.In accordance with another embodiment of the invention, an apparatus is disclosed for practicing the method.

Abstract: The present invention is directed to single crystal superalloys of eutectic or near-eutectic composition. The high temperature mechanical properties of the superalloys of the invention are improved by precipitation of dispersoids of a phase of the eutectic into the single crystal matrix during thermal treatment subsequent to solidification of the single crystal from the superalloy melt. During solidification, the growth of the dispersed phase is suppressed.

Abstract: A non-contacting sensing method and apparatus is disclosed for positioning a surface, such as the surface of a workpiece. A collimated light beam is projected through a lens having a known focal length onto the surface. Suitable means such as a television camera is positioned to receive light reflected from the surface and provide a series of video pulses, wherein the number of pulses produced per television frame scan corresponds to the size of the light image focused onto the photosensitive element within the camera. The position of the surface relative to the lens is varied until the number of pulses produced per scan is at a minimum.

Abstract: A non-contacting sensing system for measuring dimensions or determining the position of an object, such as a workpiece in an automated machining process. A small diameter light beam is projected and focused at a predetermined location. A television camera, positioned to view the location, receives light reflected from the location and generates a video signal. This signal is provided to a circuit which detects changes in signal magnitude indicative of a change in position of the object relative to the predetermined location.

Abstract: The invention relates to a type of proximity sensor. In one form, two sinusoidal signals travel along two transmission lines near an object. When the distance between one or both of the lines and the object changes, the speed of travel of one or both of the signals changes. There is a correlation between the speed change and the distance, thus allowing one to infer distance from speed change. One way to measure the speed change is to measure the phase relationship between the two signals.

Abstract: A method for replacing a damaged or defective section of a length of original piping or tubing located within a structrue such as the turbine of a jet engine wherein access to the tubing is limited, and replacing such damaged section with a new section of tubing comprises inserting a cutter mounted at one end of a flexible shaft into the interior of the original tubing and rotating the shaft to cut out and remove the damaged section of tubing leaving at least one stub section of original tubing. The stub sections of original tubing are then prepared for welding or brazing to a section of replacement tubing with a series of tools each mounted to an elongated shaft. These tools include a chamfering tool, a deburring tool, and a polishing tool.